Banning chemical weapons

During World War I, Germany, France, the United Kingdom, and Russia developed a wide array of chemical arms, including choking, blister, blood, and irritant agents. During World War II, Germany developed nerve agents such as toman, soman, and sarin. After World War II, the British invented VX, a more persistent nerve agent that eventually was deployed by the United States and the Soviet Union.

The World War I chemical agents are referred to as first-generation weapons, the World War II nerve agents are called second-generation weapons, and Cold War chemical agents (such as VX) are known as third-generation weapons. Part of the U.S. arsenal during the Cold War also included CS, a riot-control agent, and BZ, an incapacitant, as well as sarin and VX. The Soviet Union also had a complete chemical weapons arsenal, including “classic” agents from the first, second, and third generation, all of which are now banned by the CWC.

According to some interpretations, the CWC does not cover fourth-generation chemical weapons, so-called nontraditional agents (NTAs), such as some of the binary nerve agents known as “novichoks.” There is evidence that Russia inherited NTAs from the former Soviet arsenals.

Negotiations to secure a multilateral chemical disarmament treaty began in the early 1960s at the United Nations. Issues that separated the sides were the kinds of verification procedures for checking on treaty compliance, whether all or part of the weapons stocks should be dismantled, and the sanctions to be levied against violators. Real progress did not take place until the period 1986–91, when relations between the Soviet Union and the United States improved after the rise to power of Soviet leader Mikhail Gorbachev. With the dissolution first of the Warsaw Pact in 1989 and then of the Soviet Union itself in 1991, a real convergence of political and diplomatic views was made possible. In 1990 bilateral reductions and limits were negotiated in which each state agreed to a limit of 5,000 tons of chemical agents in its chemical weapons arsenal. By 1993 the former enemies were finally willing to agree to a robust on-site verification regime featuring challenge inspections of undeclared sites, a total ban on chemical weapons, and a total dismantling of their stockpiles.

The United Nations Conference on Disarmament adopted the Chemical Weapons Convention (CWC) on September 3, 1992, and the treaty was opened to signature by all states on January 13, 1993. The CWC entered into force on April 29, 1997, 180 days after the deposit of the 65th instrument of ratification (such as passage by a national assembly).

At the time that the United States and Russia signed the CWC, Russia declared 40,000 metric tons of chemical weapon agents and the United States 30,000 metric tons—stockpiles that dwarfed the combined arsenals of the rest of the world. All were to be destroyed, according to CWC guidelines, by the year 2012. In the early 1990s the U.S. Cooperative Threat Reduction Program was launched to help the states of the former Soviet Union demilitarize their chemical, biological, and nuclear facilities and arsenals and to employ the scientists and technicians from those programs in other, more productive peacetime activities. Despite such efforts, both countries fell behind schedule and announced that they would not be able to meet the 2012 deadline. The United States was on a trajectory to finish the job by 2021, and Russia declared it would finish its parallel effort in 2015.

All other signatories to the CWC reportedly eliminated their stockpiles, though some states subsequently declared stockpiles that they had previously denied existed. Libya is a case in point. In 2004 Libya decided to part with its chemical and nuclear weapons programs and invited the United States and the United Kingdom to help it dismantle both. Significant progress was made in destroying mustard gas and precursors to other chemical weapons before Libya was paralyzed by civil strife in 2011.

United Nations inspection teams entered Iraq after the Persian Gulf War ended in early 1991. Some 40,000 Iraqi chemical weapons were then found and destroyed, and a bunker containing thousands of possibly war-damaged weapons was sealed. After the U.S. invasion of Iraq in 2003, no major stockpile of chemical weapons or dedicated facilities for their manufacture were found in Iraq, contrary to the United States’ contention before the invasion. A very few chemical rounds were found among arms storage sites in Iraq, but they were thought to be left over from the Iran-Iraq War. Upon becoming a signatory to the CWC in 2009, Iraq acknowledged its obligation to dispose of its remaining damaged weapons—a complicated and dangerous effort that would take years to complete.

Proliferation and detection of chemical weapons programs

Chemical weapons proliferation

The Chemical Weapons Convention has resulted in the elimination of huge stocks of chemical weapons once held by the principal adversaries of the Cold War. Nevertheless, intelligence services of various countries have reported an increase in the number of states with active chemical weapons programs. Some 20 countries were reportedly working on chemical weapons at the beginning of the 21st century, as opposed to only five such states in the 1960s.

Regimes seek to acquire chemical weapons for a number of reasons. First, they may decide that having such lethal weapons will allow them to “level the playing field” against an adversary with a stronger conventional military force. Second, they may wish to deter attacks by rivals, holding them at bay with the threat of a chemical weapons strike in retaliation. Having one type of weapon of mass destruction might deter the use of the same or another type by a rival. Third, chemical weapons, like other mass-casualty weapons such as nuclear and biological arms, may be designed for regime survival in the event that a country is losing a conventional conflict. In this case, possession of chemical warfare capabilities might provide endgame bargaining leverage to establish better terms. For example, in the Iran-Iraq War, Iraq’s use of Scud ballistic missiles (with the potential to deliver chemical warheads) against Iranian cities caused major panic in those metropolitan centres and helped persuade the Iranian government to agree to a cease-fire sought by Iraq. Fourth, chemicals can be used as terror weapons to lower enemy morale and weaken support for the rival’s war effort. Finally, chemical weapons can be used against unprotected rebellious groups inside a country, as Ṣaddām Ḥussein illustrated in his chemical weapon strikes against the Kurdish city of Halabjah.

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